如何在wpf treeview控件上启用平滑滚动

<Style x:Key="SmoothScrollTreeViewStyle" TargetType="TreeView">
    <Setter Property="ScrollViewer.CanContentScroll" Value="False"/>
    <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
    <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="TreeView">
                <Border Background="{TemplateBinding Background}"
                        BorderBrush="{TemplateBinding BorderBrush}"
                        BorderThickness="{TemplateBinding BorderThickness}">
                    <ScrollViewer x:Name="PART_ScrollViewer"
                                  Focusable="False"
                                  HorizontalScrollBarVisibility="{TemplateBinding ScrollViewer.HorizontalScrollBarVisibility}"
                                  VerticalScrollBarVisibility="{TemplateBinding ScrollViewer.VerticalScrollBarVisibility}"
                                  CanContentScroll="{TemplateBinding ScrollViewer.CanContentScroll}"
                                  PanningMode="Both"
                                  PanningRatio="2">
                        <ItemsPresenter/>
                    </ScrollViewer>
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

<TreeView Style="{StaticResource SmoothScrollTreeViewStyle}">
    <!-- TreeView的内容 -->
</TreeView>